熔盐电解法制备纳米碳管及纳米线

以LiCl、LiCl+SnCl2等为熔盐电解质,采用电解石墨的方法制备了纳米碳管和纳米线,并运用TEM、XRD、EDS等分析手段对产物的形貌和结构进行了表征.结果表明,熔盐成分对电解产物的形态和性质有显著影响.在LiCl熔盐中可得到直径为75～100nm的纳米碳管;在LiCl+1.0%SnCl2熔盐中可生成β-Sn填充的纳米碳管.XRD测试表明,电解制备的β-Sn纳米线经氧化处理后在碳管内可转变为SnO2,其晶体结构为四方晶系,直径为20～50 nm.电解过程中Li+在石墨阴极上反应生成的LiC6化合物对纳米碳结构的形成具有重要作用.

Preparation of Carbon Nanotubes and Nanowires by Electrolysis in Molten Salts

Carbon nanotubes and metal nanowires were formed in situ during the electrolysis of graphite cathode using LiCl, LiOHand LiCl/SnCl2 melts as electrolyte, respectively. The structure and morphology were characterized by TEM, XRD and EDS analyses. TEM images showed that the prepared materials varied with the nature and composition of the melts. Carbon nanotubes were formed electrolytically in the LiCl melt with the diameters in the range of 75~100 nm, but β-Sn-filled carbon nanotubes were generated in molten LiCl+1.0%SnCl2 mixtures. Followed by subsequent oxidation in the air, β-Sn nanowires were converted into SnO2 in carbon nanotubes, which was identified by XRD analysis. The obtained SnO2 nanowires were of tetragonal structure ranging from 20~50 nm in diameter. It was implied that the occurrence of LiC6produced from cathodic reactions had significant influence on the formation of carbon nanostructure during electrolysis.